Publications by authors named "B Y van Heyst"

Laying hens are chronically exposed to high levels of ammonia (NH3), one of the most abundant aerial pollutants in poultry houses. Tests for aversion to NH3 in laying hens have used artificially sourced NH3/air mixtures (i.e.

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In 1999, the National Emission Inventory and Project Task Group developed particulate matter emission inventories for the Canadian poultry industry using Canadian poultry census data and emission factors for all types of poultry operations based on U.S. Environmental Protection Agency and British Columbia/Greater Vancouver Regional District data [MOE.

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As the contamination of beta-hexachlorocyclohexane (beta-HCH) in the Arctic air, seawater, and biota is an environmental concern, there is a need for emission inventories of beta-HCH to be used by the modeling community to predict the fate and transport of beta-HCH. This paper presents such emission inventories for beta-HCH. The total global usage of beta-HCH between 1945 and 2000 is estimated at 850 kt, 230 kt of which was emitted to the atmosphere over the same time period.

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Emissions of volatile mercury species from natural soils are believed to be a significant contributor to the atmospheric burden of mercury, but only order-of-magnitude estimates of emissions from these sources are available. The scaling-up of mercury flux measurements to regional or global scales is confounded by a limited understanding of the physical, chemical and biochemical processes that occur in the soil, a complex environmental matrix. This study is a first step toward the development of an air-surface exchange model for mercury (known as the mercury emission model (MEM)).

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Chlamydiazyme (Abbott), an enzyme-linked immunoassay (EIA), was evaluated using cell culture on Hela 229 cells as the method of reference. Samples were acquired from 611 female and 280 male patients attending the outpatient clinic for sexually transmitted disease at the University Hospital in Rotterdam, The Netherlands. The prevalences of chlamydia culture-positive female and male patients were 7.

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